My grandmother’s recipe for this used frozen broccoli and had crushed potato chips on top. In the quest to use up almost the last of a huge bag of fresh broccoli from the big box store, I made Chicken Divan with fresh broccoli and frozen boneless skinless chicken breasts. I thawed the chicken in warm water over low heat while fixing everything else, then sautéed the chicken breasts after sprinkling salt and garlic pepper on them.
The recipe only calls for 4 cups of broccoli but I used at least 5. If you’re trying to lessen the amount of meat you eat and increase the quantity of vegetables, playing around with the ratios in casseroles like this is an easy way to do it.
You could use low fat or non-fat canned cream of mushroom soup or make your own cream soup.